Unexplained postoperative retinal hemorrhage after 23-gauge sutureless vitrectomy

We report five cases of unexplained retinal hemorrhage after 23-gauge sutureless vitrectomy. A 23-gauge sutureless vitrectomy was performed for four cases of macular holes (MH) and one case of macular hole retinal detachment (MHRD). Retinal hemorrhages were observed on the first day after surgery and disappeared within several months without leaving any recognizable damage. We speculate that the retinal hemorrhages might have resulted from repeated collapse of the globe through a cannula under air perfusion, but other causes such as retinal vein congestion by face-down positioning are also possible

Evaluation of a partial retinal surface tear by optical coherence tomography

Differential diagnosis of retinal hemorrhage and partial tear of the retinal surface may be difficult in some cases. A 62-year-old woman was mistakenly followed-up for small retinal hemorrhages for more than 1 year. Blocked fluorescence specific to retinal hemorrhage was not observed by fluorescein angiography (FAG). Optical coherence tomography (OCT) clearly showed defects of the retinal surface indicating partial tears of the surface at the vitreo-retinal juncture and not hemorrhage. OCT is a useful and noninvasive device for the differential diagnosis of retinal hemorrhage and partial tear of the retinal surface

Trajectory Tracking Control of Dual-PAM Soft Actuator with Hysteresis Compensator

Soft robotics is a swiftly evolving field. Pneumatic actuators are suitable for driving soft robots because of their superior performance. However, their control is challenging due to the hysteresis characteristics. In response to this challenge, we propose an adaptive control method to compensate for the hysteresis of soft actuators. Employing a novel dual pneumatic artificial muscle (PAM) bending actuator, the innovative control approach abates hysteresis effects by dynamically modulating gains within a traditional PID controller corresponding to the predicted variation of the reference trajectory. Through experimental evaluation, we found that the proposed control method outperforms its conventional counterparts regarding tracking accuracy and response speed. Our work reveals a new direction for advancing model-free control in soft actuators.Comment: This paper has been published in the IEEE Robotics and Automation Letters ,DOI 10.1109/LRA.2023.3334098, copyright has been transfferd to the IEEE. Final version is available at IEEE Xplor

Two Degree of Freedom Adaptive Control for Hysteresis Compensation of Pneumatic Continuum Bending Actuator

Soft robotics, with their inherent flexibility and infinite degrees of freedom (DoF), offer promising advancements in human-machine interfaces. Particularly, pneumatic artificial muscles (PAMs) and pneumatic bending actuators have been fundamental in driving this evolution, capitalizing on their mimetic nature to natural muscle movements. However, with the versatility of these actuators comes the intricate challenge of hysteresis - a nonlinear phenomenon that hampers precise positioning, especially pronounced in pneumatic actuators due to gas compressibility. In this study, we introduce a novel 2-DoF adaptive control for precise bending tracking using a pneumatic continuum actuator. Notably, our control method integrates adaptability into both the feedback and the feedforward element, enhancing trajectory tracking in the presence of profound nonlinear effects. Comparative analysis with existing approaches underscores the superior tracking accuracy of our proposed strategy. This work discusses a new way of simple yet effective control designs for soft actuators with hysteresis properties.Comment: Submitted to IEEE Conference on Robotics and Automation (ICRA 2024), Under Revie

Design and synthesis of amidine-type peptide bond isosteres: application of nitrile oxide derivatives as active ester equivalents in peptide and peptidomimetics synthesis.

Amidine-type peptide bond isosteres were designed based on the substitution of the peptide bond carbonyl (C=O) group with an imino (C=NH) group. The positively-charged property of the isosteric part resembles a reduced amide-type peptidomimetic. The peptidyl amidine units were synthesized by the reduction of a key amidoxime (N-hydroxyamidine) precursor, which was prepared from nitrile oxide components as an aminoacyl or peptidyl equivalent. This nitrile oxide-mediated C-N bond formation was also used for peptide macrocyclization, in which the amidoxime group was converted to peptide bonds under mild acidic conditions. Syntheses of the cyclic RGD peptide and a peptidomimetic using both approaches, and their inhibitory activity against integrin-mediated cell attachment, are presented

Usefulness of helical computed tomography in diagnosing pulmonary vein stenosis in infants.

We investigated the usefulness of helical computed tomography(CT)in the morphological diagnosis of pulmonary vein stenosis, particularly that in infants and small children. In total, 20 helical CT examinations were performed in 10 post-operative cases of Total Anomalous Pulmonary Venous Drainage(TAPVD), 3 cases of single right ventricle, and 1 case of single left ventricle. In all cases, distinct morphological imaging was possible. Pulmonary vein stenosis could be categorized into three types: (1)stenosis from the anastomosis of the common pulmonary vein (CPV)-the left atrium (LA) to the peripheral pulmonary vein; (2) stenosis only at the anastomosis of CPV-LA; and (3) stenosis due to compression by nearby organs. Coronal views by multiplanar reconstruction (MPR) provided morphological information along the up-down direction of the body axis. Morphological diagnosis of pulmonary vein stenosis is important in deciding prognosis and therapeutic regimens, and helical CT was considered useful for such diagnosis in our 14 young patients.</p

Fixed point observation for daily snow surface monitoring along a latitudinal transect from the coast to the inland of Antarctica using camera images

The Tenth Symposium on Polar Science/Ordinary sessions: [OM] Polar Meteorology and Glaciology, Wed. 4 Dec. / Entrance Hall (1st floor) , National Institute of Polar Researc